<?php
 namespace app\common;

 use think\Paginator;

 class LayuiPager extends Paginator
 {
    protected $uri;
    /**
    * 上一页按钮
    * @param string $text
    * @return string
    */
    protected function getPreviousButton($text = "上一页")
    {

        if ($this->currentPage() <= 1) {
            return $this->getDisabledTextWrapper($text);
        }

        $url = $this->new_url(
            $this->currentPage() - 1
        );

        return $this->getPageLinkWrapper($url, $text);
    }

    /**
    * 下一页按钮
    * @param string $text
    * @return string
    */
    protected function getNextButton($text = '下一页')
    {
        if (!$this->hasMore) {
            return $this->getDisabledTextWrapper($text);
        }

        $url = $this->new_url($this->currentPage() + 1);

        return $this->getPageLinkWrapper($url, $text);
    }

    /**
    * 页码按钮
    * @return string
    */
    protected function getLinks()
    {
        if ($this->simple)
            return '';

        $block = [
            'first' => null,
            'slider' => null,
            'last' => null
        ];

        $side = 3;
        $window = $side * 2;

        if ($this->lastPage < $window + 6) {
            $block['first'] = $this->getUrlRange_new(1, $this->lastPage);
        } elseif ($this->currentPage <= $window) {
            $block['first'] = $this->getUrlRange_new(1, $window + 2);
            $block['last'] = $this->getUrlRange_new($this->lastPage - 1, $this->lastPage);
        } elseif ($this->currentPage > ($this->lastPage - $window)) {
            $block['first'] = $this->getUrlRange_new(1, 2);
            $block['last'] = $this->getUrlRange_new($this->lastPage - ($window + 2), $this->lastPage);
        } else {
            $block['first'] = $this->getUrlRange_new(1, 2);
            $block['slider'] = $this->getUrlRange_new($this->currentPage - $side, $this->currentPage + $side);
            $block['last'] = $this->getUrlRange_new($this->lastPage - 1, $this->lastPage);
        }

        $html = '';

        if (is_array($block['first'])) {
            $html .= $this->getUrlLinks($block['first']);
        }

        if (is_array($block['slider'])) {
            $html .= $this->getDots();
            $html .= $this->getUrlLinks($block['slider']);
        }

        if (is_array($block['last'])) {
            $html .= $this->getDots();
            $html .= $this->getUrlLinks($block['last']);
        }

        return $html;
    }

    /**
    * 渲染分页html
    * @return mixed
    */
    public function render()
    {
        if ($this->hasPages()) {
            if ($this->simple) {
                return sprintf(
                    '<ul class="page">%s %s</ul>',
                    $this->getPreviousButton(),
                    $this->getNextButton()
                );
            } else {
                return sprintf(
                    '<ul class="pagination">%s %s %s %s</ul>',
                    $this->getPreviousButton(),
                    $this->getLinks(),
                    $this->getNextButton(),
                    $this->getTotal($this->total)
                );
            }
        }
    }

    /**
    * 生成一个可点击的按钮
    *
    * @param  string $url
    * @param  int $page
    * @return string
    */
    protected function getAvailablePageWrapper($url, $page)
    {
        if ($page == '上一页')
            return '<li><a href="' . htmlentities($url) . '" class="laypage-prev">' . $page . '</a></li>';
        else if ($page == '下一页')
            return '<li><a href="' . htmlentities($url) . '" class="laypage-next">' . $page . '</a></li>';
        else
            return '<li><a href="' . htmlentities($url) . '">' . $page . '</a></li>';
    }

     /**
      * 生成一个禁用的按钮
      *
      * @param  string $text
      * @return string
      */
    protected function getDisabledTextWrapper($text)
    {
        return '<li><a class="disabled" >' . $text . '</a></li>';
    }

    /**
    * 生成一个激活的按钮
    *
    * @param  string $text
    * @return string
    */
    protected function getActivePageWrapper($text)
    {
        return '<li class="active"><span>' . $text . '</span></li>';
    }

    /**
    * 生成省略号按钮
    *
    * @return string
    */
    protected function getDots()
    {
        return $this->getDisabledTextWrapper('...');
    }

    /**
    * 批量生成页码按钮.
    *
    * @param  array $urls
    * @return string
    */
    protected function getUrlLinks(array $urls)
    {
        $html = '';

        foreach ($urls as $page => $url) {
            $html .= $this->getPageLinkWrapper($url, $page);
        }

        return $html;
    }
     
    protected function getUrlRange_new($start,$end)
    {
        $urls = [];

        for ($page = $start; $page <= $end; $page++) {
            $urls[$page] = $this->new_url($page);
        }

        return $urls;
    }
    /**
    *  生成总条数
    * @param $num
    * @return string
    */
    protected function getTotal($num)
    {
        return '<li class="disabled"><span>共'.$num.'条</span></li>';
    }
    
    /**
    * 生成普通页码按钮
    *
    * @param  string $url
    * @param  int $page
    * @return string
    */
    protected function getPageLinkWrapper($url, $page)
    {
        if ($page == $this->currentPage()) {
            return $this->getActivePageWrapper($page);
        }

        return $this->getAvailablePageWrapper($url, $page);
    }
     
    /**
    * 获取url
    */
    private function getUri(){
        $url=$_SERVER["REQUEST_URI"].(strpos($_SERVER["REQUEST_URI"], '?')?'':"?");
        $parse=parse_url($url);
 
        if(isset($parse["query"])){
            parse_str($parse['query'],$params);
            unset($params["page"]);
            $url=$parse['path'] . '?' . http_build_query($params) .'&';
        }else{
            $url=$parse['path'] . '?';
        }
 
        $this->uri = $url;
 
    }
    
    function new_url($page) {
        if (!$this->uri) {
            $pageVar = 'page';
            $get = input('get.');
            unset($get[$pageVar]);
            $get[$pageVar] = '';

            $this->uri = request()->baseUrl().'?' . http_build_query($get);
        }

        return $this->uri . $page;
    }

 }